I was the woman in this scenario SO many times. My xh used to get photos out of me when young (and thin - his main focus) and literally show them to other guys, saying "look how beautiful she was" - they always cringed and had no idea how to handle it. He was desperate to show that when he "picked" me I was acceptable, so when I was bigger that wasn't down to his poor choice. He did it to mutual friends in couples situations, to much younger employees (both they and I wanted to die of embarrassment).
There were numerous occasions but the photo ones spring to mind. Nobody ever called him out at the time. None of the women, if present, ever spoke to me about it but their pity and embarrassment was palpable.
Over the years, three men approached me privately, more than once each, saying something like "I've been feeling awful since Sat, I should have called him out on what he said but didn't want to cause a scene/spotlight it/whatever". Every time I said not your job, I understand, don't worry, my problem etc.
One of those men is still ostensibly friends with xh and new partner to this day. (She's thin, so his ego is ok). He was someone who was so worried about me at one point he rang an old friend to check on me (but still wouldn't step in, I think we both had feelings for each other we never acted on and he didn't want to overstep/upset his wife by seeming to care). Another is still in touch with him but much more friendly with me and my now dh and very critical of exh. A third barely ever sees either of us but is polite to him socially.
I totally understand why nobody wanted to insert themselves into that dynamic but I wish many more people had stood up for me to my xh. It was a really fucking lonely place to be with everyone pretending all was well and therefore condoning it. I might have got away sooner with more support.